# Significant creep-strength improvement in modified 9Cr-1Mo steel via microstructural control through laser powder bed fusion

https://mdr.nims.go.jp/datasets/7deea76a-2be4-482e-8d17-2ec63c0dd805

## File

- [1-s2.0-S2214860424004913-main.pdf](https://mdr.nims.go.jp/filesets/c46367bb-9f2e-4d66-a690-369ada3deb21/download) ([Detail](https://mdr.nims.go.jp/filesets/c46367bb-9f2e-4d66-a690-369ada3deb21.md))

## Id

7deea76a-2be4-482e-8d17-2ec63c0dd805

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2024-09-25T08:03:45.104089Z

## Updated at

2024-09-26T03:30:07.923494Z

## Published at

2024-09-26T03:30:08.905086Z

## Doi



## First published url

https://doi.org/10.1016/j.addma.2024.104445

## Date published

2024-09-18

## Recorded date published

2024-8

## Resource type

journal_article

## Manuscript type

vor

## Collection



## Title

- title: Significant creep-strength improvement in modified 9Cr-1Mo steel via microstructural
    control through laser powder bed fusion
  title_type: original
  lang: en

## Description

- description: Modified 9Cr-1Mo steel was manufactured using laser powder bed fusion
    (LPBF). The as-built LPBF-sample microstructure comprised columnar δ-ferrite grains
    and fine martensite grains. The δ-ferrite was a unique phase that formed under
    the significantly rapid LPBF-induced solidification. Creep testing was performed
    for the LPBF sample at 923 K for up to 10,000 h. The LPBF-sample time-to-rupture
    and minimum creep rate were at least 10 times longer and 100 times smaller, respectively,
    than those of conventional modified 9Cr-1Mo steels at 923 K under 100 MPa. Microstructural
    characterization of the creep-ruptured samples revealed that creep deformation
    preferentially occurred in the martensite. Thus, the δ-ferrite contributed significantly
    to the enhanced creep strength. The intrinsic creep resistance of the δ-ferrite
    phase exceeded that of the martensite. The microstructural stability of the δ-ferrite
    grains (attributed to dense MX-phase precipitation at the grain boundary) was
    a likely strengthening factor. Overall, the modified 9Cr-1Mo steel creep strength
    was successfully improved via unique microstructural control through LPBF. This
    achievement is expected to extend LPBF application as a novel microstructural
    control process for steels and alloys, avoiding the diffusional transformation
    kinetics that occur in conventional heat-treatment processes.
  description_type: abstract
  lang: und

## Creator

- name: Tomotaka Hatakeyama
  role: author
  orcid: https://orcid.org/0000-0002-2904-8177
- name: Kota Sawada
  role: author
  orcid: https://orcid.org/0000-0001-7780-1648
- name: Masahiro Kusano
  role: author
  orcid: https://orcid.org/0000-0002-5061-0195
- name: Makoto Watanabe
  role: author
  orcid: https://orcid.org/0000-0002-5064-9583

## Contact agent



## Publisher

organization: Elsevier BV

## Managing organization



## Keyword

- subject: Creep
  schema: not_defined
- subject: Ferritic steels
  schema: not_defined
- subject: Laser powder bed fusion
  schema: not_defined
- subject: Precipitation
  schema: not_defined
- subject: δ-ferrite
  schema: not_defined

## Rights

- identifier: https://creativecommons.org/licenses/by-nc-nd/4.0/

## Other identifier(s)



## Data origin



## Embargo



## Journal

- title: Additive Manufacturing
  issn: '22148604'
  volume: '93'
  article_number: '104445'

## Conference



## Related item



## Funding

- funder_name: Chubu Electric Power Co Inc
- funder_name: Japan Boiler Association

## Instrument



## Instrument operator



## Instrument managing organization



## Measurement method



## Specimen



## Chemical composition



## Structure for specimen



## Structural feature for specimen



## Specific property for specimen



## Process for specimen treatment



## Computational method



## Energy level/transition state



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## Custom property



## Fileset

- id: c46367bb-9f2e-4d66-a690-369ada3deb21
  filename: 1-s2.0-S2214860424004913-main.pdf
  content_type: application/pdf
  size: 18331663
  md5: 35aaa822ba3de222889e8dca2d83e783

## Thumbnail

fileset_id: c46367bb-9f2e-4d66-a690-369ada3deb21
filename: 1-s2.0-S2214860424004913-main.pdf